Intra-parotid Facial Nerve Imaging in Parotidectomy

Samsung Medical Center

Status: Completed

Conditions: Facial Nerve Paresis; Parotid Tumors

Treatments: Diagnostic Test: 3D-DESS MRI (3 dimensional double echo steady state MRI)

Study type: Interventional

Funder types: Other

Identifiers

NCT03822728

2017-07-084

Details and patient eligibility

About

In this study, the investigators will evaluate the clinical usefulness of 3 dimensional double echo steady state MRI (3D-DESS MRI) for functional preservation of the facial nerve during parotidectomy. Preoperative 3D-DESS MRI imaging can provide information about the anatomical relationship between the tumor and the facial nerve in the parotid gland.

Because the risk of postoperative facial weakness is relatively high in the deep-seated parotid tumors, the investigators will exclude the patients with the superficial parotid tumors (determined by preoperative CT or US) and only include the patients with deep seated parotid tumors in this trial.

The main outcome of our study is the incidence of immediate postoperative facial weakness, and the secondary outcome is the incidence of facial weakness at postoperative 6 months.

Full description

Surgical removal of tumors arising from the parotid gland (benign or malignant) is treatment of choice. However, the most detrimental complication of parotidectomy is facial weakness or facial nerve palsy, because the facial nerve crosses in the mid-portion of the parotid gland.

Numerous studies indicated the incidence of temporary facial weakness as 5-45% and permanent facial palsy as 0-15% after parotidectomy. To reduce this complication, the investigators will apply the modern technique of MRI imaging to inform the anatomical relationship between the tumor and the facial nerve within the parotid gland preoperatively. Three dimensional double echo steady state MRI imaging (3D-DESS MRI) has been reported useful for the intra-parotid facial nerve imaging.

Thus, the investigators will evaluate the clinical usefulness of 3D-DESS MRI for functional preservation of the facial nerve during parotidectomy. Preoperative 3D-DESS MRI imaging can provide information about the anatomical relationship between the tumor and the facial nerve in the parotid gland.

In the retrospective series, the investigators found that there were 25.6% temporary facial weakness and 10.3% permanent (> 6 months) facial weakness after parotidectomy for deep-seated parotid tumors (plus tumors located in both deep and superficial parotid gland); whereas 6.7% and 3.6% facial weakness respectively for superficially located parotid tumors. Because the risk of postoperative facial weakness is relatively high in the deep-seated parotid tumors, the investigators will exclude the patients with the superficial parotid tumors (determined by preoperative CT or US) and only include the patients with deep seated parotid tumors in this trial.

The main outcome of our study is the incidence of immediate postoperative facial weakness, and the secondary outcome is the incidence of facial weakness at postoperative 6 months.

Enrollment: 270 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Parotid tumors subject to the surgery (parotidectomy)
• Parotid deep lobe tumors or tumor located in both superficial and deep parotid glands (Tumor medial to the facial nerve line, a line connecting the lateral border of mandible and the posterior belly of digastric muscle on CT scans or tumors crossing the facial nerve line on CT scans)
• Benign or malignant tumors
• Any size of parotid tumors

Exclusion criteria

• Superficially located parotid tumor on CT or US (Tumor lateral to the facial nerve line, a line connecting the lateral border of mandible and the posterior belly of digastric muscle on CT scans)
• Previous parotid surgery in the affected parotid gland (Revision parotid surgery)
• Preoperative facial nerve palsy
• Cases with the facial nerve sacrifice during surgery for oncological purpose (malignancy)

Trial design

Primary purpose: Prevention

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

270 participants in 2 patient groups

Without 3D-DESS MRI

No Intervention group

Description:

As for deep seated tumors in preoperative CT or US (or tumors in both superficial and deep parotid glands), the patients will undergo surgery without 3D-DESS MRI (currently routine practice).

With 3D-DESS MRI

Experimental group

Description:

As for deep seated tumors in preoperative CT or US (or tumors in both superficial and deep parotid glands), preoperative 3D-DESS MRI will be additionally performed to delineate the intra-parotid facial nerve.

Treatment:

Diagnostic Test: 3D-DESS MRI (3 dimensional double echo steady state MRI)